Feedthrough assemblies

ABSTRACT

Various embodiments of a feedthrough assembly and methods of forming such assemblies are disclosed. In one or more embodiments, the feedthrough assembly can include a non-conductive substrate and a feedthrough. The feedthrough can include a via from an outer surface to an inner surface of the non-conductive substrate, a conductive material disposed in the via, and an external contact disposed over the via on the outer surface of the non-conductive substrate. The external contact can be electrically coupled to the conductive material disposed in the via. And the external contact can be hermetically sealed to the outer surface of the non-conductive substrate by a bond surrounding the via. In one or more embodiments, the bond can be a laser bond.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.62/096,677, filed on Dec. 24, 2014. The disclosure of the aboveapplication is incorporated herein by reference in its entirety.

BACKGROUND

Various systems require electrical coupling between electrical devicesdisposed within a hermetically sealed enclosure and external devices.Oftentimes, such electrical coupling needs to withstand variousenvironmental factors such that a conductive pathway or pathways fromthe external surface to within the enclosure remains stable. Forexample, implantable medical devices (IMDs), e.g., cardiac pacemakers,defibrillators, neurostimulators and drug pumps, which includeelectronic circuitry and battery elements, require an enclosure orhousing to contain and hermetically seal these elements within a body ofa patient. Many of these IMDs include one or more electrical feedthroughassemblies to provide electrical connection between the elementscontained within the housing and components of the IMD external to thehousing, for example, sensors and/or electrodes and/or lead wiresmounted on an exterior surface of the housing, or electrical contactshoused within a connector header, which is mounted on the housing toprovide coupling for one or more implantable leads, which typicallycarry one or more electrodes and/or one or more other types ofphysiological sensors. A physiological sensor, for example a pressuresensor, incorporated within a body of a lead may also require ahermetically sealed housing to contain electronic circuitry of thesensor and an electrical feedthrough assembly to provide electricalconnection between one or more lead wires, which extend within theimplantable lead body, and the contained circuitry.

A feedthrough assembly typically includes one or more feedthrough pinsthat extend from an interior to an exterior of the housing through aferrule. Each feedthrough pin is electrically isolated from the ferrule,and, for multipolar assemblies, from one another, by an insulatorelement, e.g., glass or ceramic, that is mounted within the ferrule andsurrounds the feedthrough pin(s). Glass insulators are typically sealeddirectly to the pin(s) and to the ferrule, e.g., by heating the assemblyto a temperature at which the glass wets the pin(s) and ferrule, whileceramic insulators are typically sealed to the pin(s) and to the ferruleby a braze joint. High temperatures are typically required to joincorrosion-resistant conductive materials with corrosion-resistantinsulative materials.

SUMMARY

In general, the present disclosure provides various embodiments of afeedthrough assembly that includes a substrate and one or morefeedthroughs. In one or more embodiments, a feedthrough can include anexternal contact disposed over a via that is formed from an outersurface to an inner surface of the substrate. The external contact canbe hermetically sealed to the outer surface of the substrate by a bondthat surrounds the via.

In one aspect, the present disclosure provides a feedthrough assemblythat includes a non-conductive substrate and a feedthrough. Thefeedthrough includes a via from an outer surface to an inner surface ofthe non-conductive substrate, a conductive material disposed in the via,and an external contact disposed over the via on the outer surface ofthe non-conductive substrate. The external contact is electricallycoupled to the conductive material disposed in the via. And the externalcontact is hermetically sealed to the outer surface of thenon-conductive substrate by a laser bond surrounding the via.

In another aspect, the present disclosure provides a method of forming afeedthrough assembly. The method includes forming a via through anon-conductive substrate, where the non-conductive substrate includes anouter surface and an inner surface; forming a conductor on the outersurface of the non-conductive substrate; and forming an external contactover the via and a portion of the conductor, where the external contactis electrically coupled to the conductor. The method further includesattaching the external contact to the outer surface of thenon-conductive substrate by a laser bond that surrounds the via andhermetically seals the external contact to the outer surface of thenon-conductive substrate; and forming a conductive material in the viathat is electrically coupled to the external contact.

In another aspect, the present disclosure provides a method of forming afeedthrough assembly. The method includes forming a conductive layer onan outer surface of a non-conductive substrate; attaching the conductivelayer to the outer surface of the non-conductive substrate by a laserbond that hermetically seals the conductive layer to the outer surface;and removing a portion of the conductive layer to form an externalcontact on the outer surface of the non-conductive substrate, where thelaser bond is between the external contact and the outer surface of thenon-conductive substrate. The method further includes forming a viathrough the non-conductive substrate between an inner surface of thenon-conductive substrate to the external contact on the outer surfacewithin the laser bond such that the laser bond surrounds the via;forming a conductor on the external contact and the outer surface of thenon-conductive substrate, where the conductor is electrically coupled tothe external contact; and forming a conductive material in the via thatis electrically coupled to the external contact.

In another aspect, the present disclosure provides a method of forming afeedthrough assembly. The method includes forming a via through anon-conductive substrate, the non-conductive substrate includes an outersurface and an inner surface; forming a conductive material in the via;and forming a conductor on the outer surface of the non-conductivesubstrate that is electrically coupled to the conductive material in thevia. The method further includes forming a conductive layer on the outersurface of the non-conductive substrate over the conductor and the via;attaching the conductive layer to the outer surface of thenon-conductive substrate by a laser bond that hermetically seals theconductive layer to the non-conductive substrate, where the laser bondsurrounds the via; and removing a portion of the conductive layer toform an external contact on the outer surface of the non-conductivesubstrate, where the laser bond is between the external contact and theouter surface of the non-conductive substrate such that the externalcontact is hermetically sealed to the outer surface of thenon-conductive substrate. The external contact is electrically coupledto the conductor and the conductive material in the via.

In another aspect, the present disclosure provides a feedthroughassembly that includes a non-conductive substrate and a feedthrough. Thefeedthrough includes a via from an outer surface to an inner surface ofthe non-conductive substrate, a conductive material disposed in the via,and an external contact disposed over the via on the outer surface ofthe non-conductive substrate. The external contact is electricallycoupled to the conductive material disposed in the via. Further, theexternal contact is hermetically sealed to the outer surface of thenon-conductive substrate by a bond line surrounding the via.

These and other aspects of the present disclosure will be apparent fromthe detailed description below. In no event, however, should the abovesummaries be construed as limitations on the claimed subject matter,which subject matter is defined solely by the attached claims, as may beamended during prosecution.

BRIEF DESCRIPTION OF THE DRAWINGS

Throughout the specification, reference is made to the appendeddrawings, where like reference numerals designate like elements, andwherein:

FIG. 1A is a schematic cross-section views of embodiments of afeedthrough assembly.

FIG. 1B is a schematic cross-section views of embodiments ofhermetically-sealed packages that include a feedthrough assembly.

FIG. 2 is a schematic plan view of a feedthrough of the feedthroughassembly of FIGS. 1A AND 1B.

FIG. 3 is a schematic cross-section view of a portion of the feedthroughassembly of FIGS. 1A AND 1B.

FIG. 4 is a schematic plan view of a feedthrough of the feedthroughassembly of FIGS. 1A AND 1B.

FIG. 5 is a schematic cross-section view of another embodiment of afeedthrough assembly.

FIG. 6 is a schematic plan view of another embodiment of a feedthroughassembly.

FIG. 7A is a schematic cross-section view of an embodiment of a methodof forming a feedthrough assembly.

FIG. 7B is a schematic cross-section view of an embodiment of a methodof forming a feedthrough assembly.

FIG. 7C is a schematic cross-section view of an embodiment of a methodof forming a feedthrough assembly.

FIG. 7D is a schematic cross-section view of an embodiment of a methodof forming a feedthrough assembly.

FIG. 7E is a schematic cross-section view of an embodiment of a methodof forming a feedthrough assembly.

FIG. 8A is a schematic cross-section view of another embodiment of amethod of forming a feedthrough assembly.

FIG. 8B is a schematic cross-section view of another embodiment of amethod of forming a feedthrough assembly.

FIG. 8C is a schematic cross-section view of another embodiment of amethod of forming a feedthrough assembly.

FIG. 8D is a schematic cross-section view of another embodiment of amethod of forming a feedthrough assembly.

FIG. 8E is a schematic cross-section view of another embodiment of amethod of forming a feedthrough assembly.

FIG. 9A is a schematic cross-section view of another embodiment of amethod of forming a feedthrough assembly.

FIG. 9B is a schematic cross-section view of another embodiment of amethod of forming a feedthrough assembly.

FIG. 9C is a schematic cross-section view of another embodiment of amethod of forming a feedthrough assembly.

FIG. 9D is a schematic cross-section view of another embodiment of amethod of forming a feedthrough assembly.

FIG. 9E is a schematic cross-section view of another embodiment of amethod of forming a feedthrough assembly.

FIG. 10 is a schematic side view of one embodiment of an implantablemedical device system.

FIG. 11 is a schematic cross-section view of the implantable medicaldevice of the system of FIG. 10.

FIG. 12 is a schematic cross-section view of a portion of anotherembodiment of a hermetically-sealed package that includes a feedthroughassembly.

FIG. 13 is a schematic cross-section view of a portion of anotherembodiment of a hermetically-sealed package that includes a feedthroughassembly.

FIG. 14A is a schematic cross-section view of embodiments ofhermetically-sealed packages that include a feedthrough assembly.

FIG. 14B is a magnified schematic cross-section view of an embodiment ofhermetically-sealed packages that include a feedthrough assembly.

FIG. 15A is a schematic cross-section view of another embodiment of amethod of forming a feedthrough assembly.

FIG. 15B is a schematic cross-section view of another embodiment of amethod of forming a feedthrough assembly.

FIG. 15C is a schematic cross-section view of another embodiment of amethod of forming a feedthrough assembly.

FIG. 15D is a schematic cross-section view of another embodiment of amethod of forming a feedthrough assembly.

FIG. 15E is a schematic cross-section view of another embodiment of amethod of forming a feedthrough assembly.

DETAILED DESCRIPTION

In general, the present disclosure provides various embodiments of afeedthrough assembly that includes a substrate and one or morefeedthroughs. In one or more embodiments, a feedthrough can include anexternal contact disposed over a via that is formed from an outersurface to an inner surface of the substrate. The external contact canbe hermetically sealed to the outer surface of the substrate by a bondthat surrounds the via.

In one or more embodiments, the feedthrough can be formed through thesubstrate using low temperature techniques that do not require the useof ferrules, glasses, or brazing materials. Further, in one or moreembodiments, the feedthrough can be formed without creating unacceptablestresses in the materials used to form the feedthrough that can becaused by the use of high temperature bonding techniques. Further, inone or more embodiments, the external contact of the feedthrough and anoptional internal contact electrically coupled to the via can be ofsufficient size and thickness to enable laser, resistance, or otherwelding and joining techniques to be utilized to electrically coupleconductors and/or electronic devices to the contacts. In addition, inone or more embodiments, the disclosed low temperature processingtechniques can also allow for internal metallization such as Ti/Ni/Audirectly on a non-conductive substrate. This can, in one or moreembodiments, facilitate the disposition of various electronic devicesdirectly onto the substrate, e.g., integrated circuits, or discretecircuit components such as filtering capacitors, diodes, resistors etc.,as will be described in one example below.

FIGS. 1A-4 are various schematic views of one embodiment of afeedthrough assembly 10. The assembly 10 includes a substrate 12 thathas an outer surface 14 and an inner surface 16. The assembly 10 alsoincludes one or more feedthroughs 18. In one or more embodiments, theassembly 10 can include an array of feedthroughs 18. The feedthroughassembly 10 can include any suitable number of feedthroughs, e.g., 1, 2,3, 4, 5, 10, 20, or more feedthroughs. Each feedthrough 18 of theassembly 10 can be substantially identical in construction. In one ormore embodiments, one or more feedthroughs can have characteristics thatare different from one or more additional feedthroughs. The feedthrough18 can include a via 20 from the outer surface 14 to the inner surface16 of the substrate 12. A conductive material 22 can be disposed in thevia 20 to provide an electrical pathway from the outer surface 14 to theinner surface 16 of the substrate 12.

The feedthrough 18 can also include an external contact 32. The externalcontact 32 can be disposed over the via 20 on the outer surface 14 ofthe substrate 12. In one or more embodiments, the external contact 32can be electrically coupled to the conductive material 22 disposed inthe via 20. The external contact 32 can be hermetically sealed to theouter surface 14 of the substrate 12, e.g., by a bond 40 that surroundsthe via 20 (as shown in FIGS. 2 and 4).

In one or more embodiments, the substrate 12 can be a non-conductive orinsulative substrate such that the external contacts 32 and anyconductors or other devices disposed on the substrate can beelectrically isolated if desired. The substrate 12 can include anysuitable material or combination of materials. In one or moreembodiments, the substrate 12 can include at least one of glass, quartz,silica, sapphire, silicon carbide, diamond, synthetic diamond, andgallium nitride, or alloys or combinations (including clad structures,laminates etc.) thereof.

Further, in one or more embodiments, the substrate 12 can besubstantially transparent at a desired wavelength or range ofwavelengths. As used herein, the phrase “substantially transparent” asit pertains to a substrate means that the substrate meets at least oneor both of the following minimal energy absorption criteria: (1) theenergy transmitted through the substantially transparent substratematerial is sufficient to activate the bonding process at the interfacevia absorption by the opaque material (e.g., interface of substrate 12and external contact 32), and (2) any energy absorbed by the transparentmaterial will not be sufficient to melt, distort, or otherwise affectthe bulk of the transparent material that is away from the bondingregion. In other words, the laser bonding techniques described hereinwill preferentially heat only the outer surface 14 (or an outer layer atthe surface 14 of the substrate 12) over the inner bulk of the substrate12 to create an enhanced bond, such as bond 40. Such a bond may exhibita relatively greater strength than the bulk strength of the substrate12. In other words, the light can be configured having any suitablewavelength provided that the substrate 12 will transmit a givenpercentage of the light that is directed at the substrate 12 topreferentially heat only the outer surface or outer layer instead of theinner bulk to create the enhanced bond. In an embodiment, the light isdirected at substrate 12 though outer surface 16 towards the outersurface 14 (or the outer layer at the surface 14 of the substrate 12).In accordance with the foregoing, a substrate that is substantiallytransparent in one exemplary embodiment will transmit at least 40% oflight that is directed at the substrate for a selected wavelength orrange of wavelengths, assuming no reflection at the air-substrateboundaries. In accordance with the foregoing, a substantiallytransparent substrate can be transmissive to light having a wavelengthin the range of 1 nm to 30 μm in one or more example embodiments. Inother embodiments, a substantially transparent substrate can be selectedbased on its transmissive properties to light of any desired wavelength.Therefore, a substantially transparent substrate 12 will allow asufficient amount of light having a predetermined magnitude to betransmitted through the inner bulk of the substrate to the outer surface14 so as to create the bond 40. In one or more embodiments, thesubstrate 12 can be substantially transmissive to at least one of UVlight, visible light, and IR light. The light can be provided by a laserthat has any suitable wavelength or range of wavelengths and anysuitable pulse width.

The substrate 12 can include any suitable dimensions, e.g., thicknesses.Further, the substrate 12 can be a single unitary substrate or multiplesubstrates joined together.

The feedthrough 18 can include the via 20 from the outer surface 14 tothe inner surface 16 of the substrate 12. The via 20 can be any suitablesize and take any suitable shape. The size and shape of the via 20 ispredicated on the thickness of the substrate 12 and the techniquesutilized to provide the conductive material that forms the electricalpathway from the outer surface 14 to the inner surface 16 of thesubstrate 12. Exemplary shapes for the via 20 may include parallelsurface walls and/or tapered surface walls as depicted in the figures.In one or more example embodiments where the substrate 12 has athickness of approximately 100 to 500 μm, a typical opening for the via20 at the outer surface 14 of the substrate 12 will be no greater than500 μm, or no greater than 250 μm, or no greater than 100 micrometers,or no greater than 80 micrometers, or no greater than 50 micrometers, orno greater than 10 micrometers. In one or more example embodiments wherethe substrate 12 has a thickness of approximately 100 to 500 μm, atypical opening for the via 20 at the inner surface 16 of the substrate12 will have a diameter that is no greater than 500 μm, or no greaterthan 250 μm, or no greater than 100 micrometers, or no greater than 80micrometers, or no greater than 50 micrometers, or no greater than 10micrometers. Of course, the diameter of the via 20 could be larger (orsmaller) than the illustrated examples based on the substrate thicknessand/or the techniques utilized to provide the conductive material thatforms the electrical pathway. Any suitable technique or combination oftechniques can be utilized to form the via 20, e.g., drilling, chemicaletching, laser etching, etc.

The feedthrough 18 can also include conductive material 22 disposed inthe via 20 to provide a conductive pathway from the outer surface 14 tothe inner surface 16 of substrate 12. The conductive material 22 caninclude any suitable conductive material or combination of conductivematerials, e.g., copper, titanium, aluminum, chromium, nickel, gold,composites (e.g., silver-filled epoxies), and combinations thereof. Theconductive material 22 can be disposed in the via 20 using any suitabletechnique or combination of techniques to provide a conductive pathwayfrom external contact 32 to one or more devices or contacts disposed onthe inner-surface side of the substrate 12. In one or more embodiments,the conductive material 22 can be disposed in the via 20 such that itsubstantially fills the via. In one or more embodiments, the conductivematerial can be disposed in the via along sidewalls of the via and theopening of the via at the external surface 14.

The feedthrough 18 can also include the external contact 32. In one ormore embodiments, the external contact 32 can be adapted to electricallycouple the feedthrough 18 to a conductor or a contact of a device, e.g.,a contact of a header of an implantable medical device. Such conductorsand contacts can be electrically coupled to the external electrode 32using any suitable technique or combination of techniques, e.g.,soldering, physical contact, welding, etc. The external contact 32 caninclude any suitable conductive material or combination of conductivematerials, e.g., copper, silver, titanium, niobium, zirconium, tantalum,stainless steel, platinum, iridium, or alloys or combinations (includingclad structures, laminates etc.) thereof. In one or more embodiments,the external contact 32 can include two or more materials, e.g.,bi-metals, clad laminates, etc.

Further, the external contact 32 can take any suitable shape orcombination of shapes. In one or more embodiments, the external contact32 can take a circular shape in a plane parallel to the outer surface 14of the substrate 12. In one or more embodiments, the external contact 32can take a rectangular shape in the plane parallel to the outer surface14 of the substrate 12. Further, the external contact 32 can take anysuitable shape or combination of shapes in a plane orthogonal to theouter surface 14 of the substrate 12, e.g., square, tapered, domed, etc.In one or more embodiments, the contact 32 can take substantially thesame shape as an external contact of one or more additional feedthroughs18. In one or more embodiments, external contact 32 can take a shapethat is different from the shape of an external contact of one or moreadditional feedthroughs 18. Further, in one or more embodiments, one ormore external contacts 32 can include complex shapes such as grooves orchannels formed in the contact to facilitate attachment of conductors orelectronic devices to the contacts.

The external contact 32 can also include any suitable dimensions. In oneor more embodiments, the contact 32 can have any suitable thickness in adirection normal to the outer surface 14 of the substrate 12. It isenvisioned that for purposes of this disclosure, the dimension of thesubstrate thickness is limited only by the fabrication techniques. Withthat in mind, in one or more example embodiments, a typical thicknesscan be at least 2 micrometers. In other example embodiments, it may bedesirable to have the thickness be less than 10 millimeters, althoughgreater thicknesses are also contemplated in accordance with embodimentsof the disclosure. The thickness of the contact 32 can be the same as ordifferent from the thickness of an external contact of one or moreadditional feedthroughs. In one or more embodiments, the externalcontact 32 can be of sufficient size and thickness to enable laser,resistance, or other welding and joining techniques to be utilized toelectrically couple conductors and/or electronic devices to the externalcontact.

In one or more embodiments, the external contact 32 can be formed ordisposed over the via 20 on the outer surface 14 of the substrate 12.For purposes of the present disclosure, the terms “form,” forming,” and“formed” will be used interchangeably with the terms “dispose,”“disposing,” and “disposed” respectively, such that the terms areconsidered to be equivalent. In other words, the external contact 32 isdisposed over the via 20 such that the contact covers the via and thevia is not visible in a plan view of the outer surface 14 of thesubstrate 12. In one or more embodiments, the external contact 32 (orany of the external contacts described herein) can be formed separatefrom the substrate 12 as a discrete member, or it could be patternedfrom a conductive sheet or foil as described below, for example, inFIGS. 7A-E, and disposed over the via 20 by attaching the formed contactto the outer surface 14 of the substrate 12.

The external contact 32 is electrically coupled to the conductivematerial 22 that is disposed in the via 20. In one or more embodiments,the external contact 32 is in direct contact with the conductivematerial 22 to electrically couple the contact to the conductivematerial. In one or more embodiments, one or more additional conductivelayers can be disposed between the external contact 32 and theconductive material 22 to electrically couple the external contact tothe conductive material.

In one or more embodiments, the external contact 32 is hermeticallysealed to the external surface 14 of the substrate 12. Any suitabletechnique or combination of techniques can be utilized to hermeticallyseal the external contact 32 to the outer surface 14 of the substrate12. For example, in one or more embodiments, the external contact 32 canbe hermetically sealed to the external surface 14 of the substrate 12 bya bond 40 (FIG. 2) that surrounds the via 20. Any suitable technique orcombination of techniques can be utilized to form this bond. Forexample, in one or more embodiments, the bond 40 can be formed using alaser to provide a laser bond. By surrounding the via 20 with the bond40 that hermetically seals the external contact 32 to the outer surface14 of the substrate 12, the via is also protected from the externalenvironment. The electrical coupling between the external contact 32 andthe conductive material 22 disposed in the via 20 is, therefore,protected, and the integrity of this electrical pathway from theexternal surface 14 of the substrate to the internal surface 16 can bemaintained. In one or more embodiments, the external contact 32 can alsobe attached to the outer surface 14 of the substrate 12 using bonds inaddition to bond 40. For example, in one or more embodiments, theexternal contact 32 can be attached to the outer surface 14 by bond 40and one or more additional bonds between the external contact 32 and theouter surface, e.g., point bonds.

FIG. 2 is a schematic plan view of a feedthrough 18 of the assembly 10of FIGS. 1A and 1B. The feedthrough 18 is shown as viewed through theinner surface 16 of the substrate 12. The feedthrough 18 includes theexternal contact 32, the via 20 including the conductive material 22disposed in the via, and the bond 40. The bond 40 hermetically seals theexternal contact 32 to the outer surface 14 of the substrate 12. Thebond 40 can take any suitable shape or combination of shapes such thatit surrounds the via 20 as shown in FIG. 2. In one or more embodiments,the bond 40 can be a bond line 41. In one or more embodiments, the bondline 41 can form a closed shape in a plane parallel to the outer surface14 of the substrate 12. As used herein, the term “closed shape” meansthat the shape is entirely enclosed such that its perimeter is unbrokenand continuous. Any suitable closed shape or shapes can be formed bybond line 41, e.g., elliptical, rectilinear, triangular, polygonal, etc.

In one or more embodiments, the bond 40 can be a bonded region thatsurrounds the via 20. The bonded region can take any suitable shape orcombination of shapes. In one or more embodiments, the bond 40 caninclude two or more shapes with one shape circumscribing the secondshape. For example, the bond 40 can include two or more concentricelliptical bond lines or rings. In such embodiments, the two or moreshapes may be isolated so that the shapes do not intersect or overlap.In one or more embodiments, the two or more shapes may intersect oroverlap along any suitable portion or portions of the shapes. In one ormore embodiments, the bond 40 can include two or more bond lines thattogether surround the via 20. For example, the bond 40 can include aseries of parallel lines that are intersected by two or more lines thatare non-parallel to the series of parallel lines.

In one or more embodiments, the bond 40 can include an interfacial layerbetween the external contact 32 and the substrate 12. It should beunderstood that the thickness of the interfacial layer, is in part, afunction of the desired strength of the bond 40 and the thickness of theexternal contact 32 and/or the substrate 12. Therefore, this interfaciallayer can have any suitable thickness in a direction normal to the outersurface 14 of the substrate 12. In accordance with one or more exampleembodiments, a typical thickness of the interfacial layer in a directionnormal to the outer surface 14 of the substrate 12 includes a thicknessof no greater than 10 nm, 100 nm, 150 nm, 200 nm, 500 nm, 1000 nm, or 10μm.

As mentioned herein, any suitable technique or combination of techniquescan be utilized to form bond 40, e.g., the techniques described inco-owned and co-filed U.S. Patent Application No. 62/096,706, entitledKINETICALLY LIMITED NANO-SCALE DIFFUSION BOND STRUCTURES AND METHODS.For example, FIG. 3 is a schematic cross-section view of a portion ofthe assembly 10 of FIGS. 1A-1B. FIGS. 1A AND 1B. In one or moreembodiments, electromagnetic radiation 70 (e.g., light such as laserlight) can be directed through substrate 12 from the inner surface 16and directed (and/or focused) at an interface of the external contact 32and the outer surface 14 of the substrate. The properties of theelectromagnetic radiation 70 can be selected based on the material ofthe substrate 12 and/or thickness and materials external contact 32 andcontrolled in a predetermined manner to form the bond. For example, theelectromagnetic radiation 70 can include laser light having a suitablewavelength or range of wavelengths and a predetermined pulse width orrange of pulse widths in one or more embodiments. The properties of theelectromagnetic radiation 70 are predicated on preferentially heatingthe interface of the substrate 12 and the contact 32 to create anenhanced bond, such as bond 40, having a relatively greater strengththan the bulk strength of the substrate 12. Accordingly, a substratethat is substantially transparent may be selected that is transmissiveto light of any desired wavelength. For example, laser light 70 caninclude UV light, visible light, IR light, and combinations thereof. Insome exemplary embodiments, some typical lasers utilized to providelaser light 70 have wavelengths in the range of 10 nm to 30 μm and apulse width in the range of 1 ns to 100 ns. In one or more embodiments,the materials for the substrate 12, the external contact 32, and thepower level, pulse width, and wavelength of the light used may beselected such that the light may not directly damage, ablate, warp, orcut the substrate and the contact, and such that the substrate and thecontact retain their bulk properties.

In general, light 70 can be provided by any suitable laser or lasersystem. For example, the laser may generate light having a relativelynarrow set of wavelengths (e.g., a single wavelength). In one or moreembodiments, the light emitted by the laser may form a collimated beamthat may not be focused at a particular point. In one or moreembodiments, the light emitted by the laser may be directed and/orfocused at a focal point at an interface of the external contact 32 andthe outer surface 14 of the substrate 12 to generate a laser bond 40.

Although the laser may provide light 70 that has a narrow range ofwavelengths, in one or more embodiments, the laser may represent one ormore devices that emit electromagnetic radiation having a wider range ofwavelengths than a single typical laser. A wide variety of devices maybe used to emit electromagnetic radiation having a narrow or wide rangeof wavelengths. In one or more embodiments, the laser may include one ormore laser devices including diode and fiber lasers. Laser sources mayalso include, e.g., carbon dioxide lasers, TI sapphire lasers, argon ionlasers, Nd:YAG lasers, XeF lasers, HeNe lasers, Dye lasers, GaAs/AlGaAslasers, Alexandrite lasers, InGaAs lasers, InGaAsP lasers, Nd:glasslasers, Yb:YAG lasers, and Yb fiber lasers. The laser device may alsoinclude one of continuous wave, modulated, or pulsed modes. Accordingly,a wide variety of laser devices may be used in the bonding process. Inone or more embodiments, a laser fluence of 1-2 J/cm² may be used, witha top hat, Gaussian, or other spatial energy profile.

A weld ring 60 can also be attached to the substrate 12. For example, abond (not shown) can be formed adjacent a perimeter 13 of the substrate12. Any suitable technique or combination of techniques can be utilizedto seal the weld ring 60 to the substrate 12, including for example, thesame technique or combination of techniques utilized to attach theexternal contact 32 to the outer surface 14 of substrate 12. In one ormore embodiments, the weld ring 60 can be hermetically sealed to thesubstrate 12.

The weld ring 60 can take any suitable shape or combination of shapesand include any suitable dimensions. In one or more embodiments, theweld ring 60 surrounds the one or more feedthroughs 18. In general, theweld ring 60 is adapted to attach the assembly 10 to an enclosure, e.g.,an enclosure of an implantable medical device. The weld ring 60 caninclude any suitable material or combination of materials, e.g., thesame materials utilized for the external contacts 32.

In one or more embodiments, the feedthrough 18 can include an internalcontact 36 disposed on the inner surface 16 of the substrate 12. Theinternal contact 36 can include any suitable material or combinationmaterials, e.g., the same materials utilized for the external contact32. Further, the internal contact 36 can take any suitable shape orcombination of shapes and have any suitable thickness in a directionnormal to the inner surface 16 of the substrate 12, e.g., the sameshapes and thicknesses as described regarding the external contact 32.

The internal contact 36 is disposed over the via 20 on the inner surface16 of the substrate 12. The contact 36 can be electrically coupled tothe conductive material 22 disposed in the via 20. The arrangement 30 ofthe external contact 32, the via 20 and the internal contact 36facilitates creation of an electrical pathway from the exterior sideadjacent to external surface 14 to the interior side adjacent the innersurface 16. In one or more embodiments, the internal contact 36 ishermetically sealed to the inner surface 16 of the substrate 12 usingany suitable technique or combination of techniques, e.g., by a bond(e.g., laser bond) that surrounds the via 20. For example, FIG. 4 is aschematic plan view of a portion of the assembly 10 of FIGS. 1A and 1B.In FIG. 4, the internal contact 36 is shown as viewed from theinner-surface side of the substrate 12. As shown in FIG. 4, the internalcontact 36 is attached to the inner surface 16 of the substrate 12 bybond 42, which is shown in dashed lines to indicate that the bond is notvisible in this view of assembly 10. Also shown in FIG. 4 is externalcontact 32 hermetically sealed to the outer surface of substrate 12 bybond 40.

In one or more embodiments, the internal contact 36 can be smaller thanthe external contact 32 in a dimension in the plane parallel to theinner surface 16. In one or more embodiments, the internal contact 36can be the same dimension or dimensions as external contact 32. In oneor more embodiments, the internal contact 36 can be larger than theexternal contact 32 in a dimension in the plane parallel to the innersurface 16. Further, the internal contact 36 can take the same shape orcombination of shapes as the external contact 32. In one or moreembodiments, the internal contact 36 can take a shape that is differentfrom the shape of the external contact 32.

In one or more embodiments, the external contact 32 can be larger thanthe internal contact 36 such that the internal contact 36 can first beattached to the inner surface 16 of substrate 12, e.g., by directinglight through the substrate from the external surface 14 to an interfaceof the internal contact 36 and the inner surface 16 of the substrate toform bond 42. The external contact 32 is connected to the outer surface14 of the substrate 12 by directing light through the internal surface16 to an interface of the external contact 32 and the outer surface 14to form bond 40 without the internal contact 36 being between the lightand the region where the bond 42 is formed. In one or more embodiments,the external contact 32 and the internal contact 36 can be relativelythe same size. In such embodiments, the external contact 32 and/or theinternal contact 36 can be attached to the substrate 12 in any suitableorder. For example, the external contract 32 can be attached to theouter surface 14 of the substrate 12 using light to form bond 40. Theinternal contact 36 can then be attached to the inner surface 16 of thesubstrate 12 by directing light at an angle into the substrate from theexternal surface 14 such that the external contact 32 does not block thelight as it forms bond 42 to attach the internal contact 36 to theinternal surface 16 of the substrate 12. In accordance with someembodiments, one or both of the external contact 32 and the internalcontact 36 is/are bonded to the outer surface 14 and the inner surface16, respectively, to form a hermetic seal. In other embodiments, onlyone of the bonds 40, 42 is formed as a hermetic seal.

As with bond 40, bond 42 can, in one or more embodiments, take anysuitable shape or combination of shapes and have any suitabledimensions, e.g., the shapes and dimensions described for bond 40. Forexample, as illustrated in FIG. 4, bond 42 can include a bond line 43.In one or more embodiments, bond 42 can include any suitable size andshaped region or regions that surround the via 20. Further, as is alsothe case with bond 40, bond 42 can include an interfacial layer betweenthe inner surface 16 of the substrate 12 and the internal contact 36.This interfacial layer can have any suitable thickness, e.g., the samethicknesses as those described for bond 40. In one or more embodiments,the bond 42 can be a laser bond.

Referring to FIG. 1B, one embodiment of a hermetically-sealed package 2is illustrated. The package 2 includes a housing 3 and a feedthroughassembly 10 that can, in one or more embodiments, form a part of thehousing. In one or more embodiments, the package 2 can also include oneor more electronic devices 6 disposed within the housing 3.

The housing 3 of the package 2 can include any suitable dimensions andtake any suitable shape or combination of shapes. In general, thehousing 3 is sized and shaped to at least partially surround theelectronic device 6. In one or more embodiments, the housing 3 caninclude one or more sidewalls 4 that can be attached to the feedthroughassembly 10 using any suitable technique or combination of techniques.The housing 3 can completely surround and enclose the electronic device6, and the feedthrough assembly 10 can be attached to the housing. Inone or more embodiments, the housing 3 can include an open side or face,and the feedthrough assembly 10 can be attached to the housing withinthis open side such that the feedthrough assembly forms a part of thehousing. The housing 3 can be a unitary housing or can include one ormore sections that are joined together using any suitable technique orcombination of techniques.

The housing 3 can include any suitable material or combination ofmaterials, e.g., metal, polymeric, ceramic, or inorganic materials. Inone or more embodiments, the housing 3 can include at least one ofglass, quartz, silica, sapphire, silicon carbide, diamond, syntheticdiamond, and gallium nitride, or alloys or combinations (including cladstructures, laminates etc.) thereof. In one or more embodiments, thehousing can include at least one of copper, silver, titanium, niobium,zirconium, tantalum, stainless steel, platinum, iridium, or alloys orcombinations (including clad structures, laminates etc.) thereof. In oneor more embodiments, the housing 3 can include the same material orcombination of materials as a substrate 12 of the feedthrough assembly10.

The package 2 can include any suitable electronic device 6 orelectronics that are disposed within the housing 2. In one or moreembodiments, the electronic device 6 can include any suitable integratedcircuit or circuits, e.g., a controller, a multiplexer, etc. It shouldbe understood that any of the electronic devices mentioned in thisdisclosure can be coupled to a power source. For instance, in one ormore embodiments, the electronic device 6 can also include a powersource 5 that is adapted to provide power to one or more integratedcircuits or devices disposed within the housing 3 or are exterior to thehousing. Any suitable power source 5 can be disposed within the housing,e.g., one or more batteries, capacitors, etc. The power source 5 can berechargeable by electrically coupling the power source to a power supplythrough the feedthrough assembly 10. In one or more embodiments, thepower source 5 can be adapted to be inductively charged by an inductivepower system that is external to the package 2.

As illustrated in FIG. 1B, the weld ring 60 can optionally provideelectrical coupling to the substrate 12. For example, weld ring 60 canbe electrically connected to a ground terminal 37 that is, for example,on an enclosure or housing of an implantable medical device thatincludes the assembly 10. In implementations where the weld ring 60material is not conductive, weld ring 60 can include one or more vias 62for electrical coupling to the ground terminal 37. In an alternativeembodiment, the weld ring 60 can be formed from a conductive materialthereby obviating the need for the vias 62. In the example embodiment ofFIG. 1B, vias 20 can be utilized to electrically couple a contact on theinner surface 16, such as internal contact 36, to the weld ring 60.

As mentioned herein, any suitable conductors or contacts can be formedon one or both of the inner surface 16 and the outer surface 14 of thesubstrate 12. For example, as shown in FIGS. 1A-1B, one or moreconductors 50 can be formed on the outer surface 14 of the substrate 12.Further, one or more conductors 52 can be disposed on the inner surface16. Any suitable number of conductors can be formed on one or both ofthe outer surface 14 and the inner surface 16. Any suitable technique orcombination of techniques can be utilized to form conductors 50, 52,e.g., chemical vapor deposition, plasma vapor deposition, physical vapordeposition, plating, etc., followed by photolithography, chemicaletching, etc. In other example embodiments, a conductive material layercan be formed on one or both of the outer surface 14 and inner surface16, and the conductive material layer can be patterned to formconductors 50, 52. Further, the conductors 50, 52 can include anysuitable conductive material or combination of conductive materials. Inone or more embodiments, the conductor 50 can electrically couple two ormore external contacts 32 together, and conductor 52 can electricallycouple two or more internal contacts 36 together. In one or moreembodiments, any of conductors 50, 52 can be coupled to one or moresuitable electronic device(s). In one or more embodiments, one or bothof conductors 50, 52 can be formed to provide an antenna forcommunication with one or more electronic devices electrically coupledto the feedthrough assembly 10. Further, in one more embodiments, one orboth of conductors 50, 52 can form an inductive coil that can beutilized to provide inductive coupling to an external inductive powersupply. For example, if the feedthrough assembly 10 is included in animplantable medical device, then conductor 50 can be used to form aninductive coil that can receive inductive energy from an externalinductive power supply to provide power to the implantable medicaldevice. Alternatively, the inductive coil can be formed by patterningthe external contacts 32.

The conductors 50, 52 of FIGS. 1A-4 can take any suitable shape orcombination of shapes and have any suitable dimensions. Further, one ormore conductors 50, 52 can electrically couple the assembly 10 toground, e.g., through coupling ground terminal 37 to an enclosure orhousing of an implantable medical device that includes the assembly 10.

Each of the conductors 50, 52 can be formed in separate steps. In one ormore embodiments, conductors on either or both of the outer surface 14and inner surface 16 can be formed simultaneously with the conductivematerial 22 disposed in the via and/or the external or internal contacts32, 36.

In one or more embodiments, one or more conductors 50, 52 can bedisposed such that the conductors are electrically coupled to a contactand the conductive material 22 disposed in the via 20. In suchembodiments, the bond 40 and/or the bond 42 would be formed between thecontact, the conductor, and the substrate 12 such that electricalcoupling between the contact, the conductor, and the conductive materialis maintained.

The feedthrough assemblies described herein can include any suitableadditional elements or devices. For example, FIG. 5 is a schematiccross-section view of another embodiment of a feedthrough assembly 100.All of design considerations and possibilities regarding the assembly 10of FIGS. 1A-4 apply equally to the assembly 100 of FIG. 5. The assembly100 includes a substrate 112 having an outer surface 114 and an innersurface 116, and one or more feedthroughs 118. The feedthrough 118 caninclude a via 120 from the outer surface 114 to the inner surface 116.Conductive material 122 can be disposed in one or more of the vias 120.The feedthrough 118 can also include an external contact 132 disposedover the via 120 on the outer surface 114 of the substrate 112, wherethe external contact is electrically coupled to the conductive material122 disposed in the via 120. In one or more embodiments, the externalcontact 132 can be hermetically sealed to the external surface 114 ofthe substrate 112 by a bond that surrounds the via 120 (e.g., bond 40 ofFIG. 4). Further, in one or more embodiments, the feedthrough 118 caninclude an internal contact 136 disposed over the via 120 on the innersurface 116, where the internal contact is electrically coupled to theconductive material 122 disposed in the via 120. The internal contact136 can be formed by any suitable technique such as sputtering, plating,evaporating, etc.

One difference between assembly 100 and assembly 10 is that assembly 100includes one or more electronic devices 180 disposed on the innersurface 116 of the substrate 112. Any suitable electronic device can bedisposed on, or connected to, the inner surface 116, e.g., capacitors,transistors, integrated circuits, including controllers andmultiplexers, etc. Further, any suitable number of electronic devices180 can be disposed on the inner surface 116. Any suitable technique orcombination of techniques can be utilized to dispose the electronicdevice 180 on the inner surface 116. In one or more embodiments, theelectronic device 180 can be formed on the inner surface 116 of thesubstrate 112. In one or more embodiments, the device 180 can be formedseparately and then attached to the inner surface 116. Any suitabletechnique or combination of techniques can be utilized to attach theelectronic device 180 to the substrate 112, e.g., a bond (e.g., bond 40of FIG. 4) can be formed between the electronic device and the innersurface 116 of the substrate.

The electronic device 180 can be electrically coupled to one or moreadditional electronic devices disposed on the inner surface 116. In oneor more embodiments, the electronic device 180 can be electricallycoupled to the conductive material 122 disposed in one or more vias. Anysuitable technique or combination of techniques can be utilized toelectrically couple the electronic device 180 to the conductive material122, e.g., one or more conductors 152 can be disposed on the innersurface 116, or the electronic device 180 can be attached to theinternal contact 136. Further, in one or more embodiments, theelectronic device 180 can be electrically coupled to other electroniccircuitry or devices disposed adjacent the substrate 112. In one or moreembodiments, the feedthrough 118 can provide a conductive pathway fromthe outer surface 114 to the electronic device 180.

As mentioned herein, the various embodiments of feedthrough assembliesdescribed herein can include any suitable number of feedthroughs. Thefeedthroughs can be disposed in any suitable arrangement. In one or moreembodiments, the feedthroughs can be disposed in a random configuration.In one or more embodiments, the feedthroughs can be disposed in anarray. For example, FIG. 6 is a schematic plan view of one embodiment ofa feedthrough assembly 210. All of the design considerations andpossibilities regarding the feedthrough assembly 10 of FIGS. 1A-4 applyequally to the feedthrough assembly 210 of FIG. 6. The feedthroughassembly 210 includes feedthroughs 218 formed through substrate 212. Thefeedthroughs 218 are disposed in an array 230. The array 230 can includeany suitable number of feedthroughs 218. And the feedthrough array 230can include any suitable arrangement of feedthroughs 232.

The various embodiments of feedthrough assemblies (e.g., feedthroughassembly 10 of FIGS. 1A-4) described herein can be formed using anysuitable technique or combination of techniques. In general, thefeedthrough assemblies described herein can be formed as singleassemblies. In one or more embodiments, two or more feedthroughassemblies can be formed on a substrate and then singulated using anysuitable technique or combination of techniques.

FIGS. 7A-E are schematic views of one embodiment of a method 300 offorming a feedthrough assembly 310. All of the design considerations andpossibilities regarding the feedthrough assembly 10 of FIGS. 1A-4 applyequally to feedthrough assembly 310 of FIGS. 7A-E. In FIG. 7A, asubstrate 312 is provided. An exterior surface 314 and an interiorsurface 316 of the substrate 312 can be prepared by polishing to removesurface deformities such as burrs, gouges, ridges, or otherirregularities. Different techniques may be used to polish outer surface314 and inner surface 316. For example, surfaces 314, 316 can bemechanically polished, chemically polished, or treated bychemical-mechanical polishing (CMP) techniques. Surfaces 314, 316 can bepolished until the surfaces exhibit comparatively low surface roughnessvalues that enhance direct bond formation. Although surfaces 314, 316may be polished to remove irregularities, the bonding process accordingto the present disclosure may not require the surfaces to be as smoothas surfaces used during typical wafer bonding techniques. Surfaces 314,316 may be cleaned to remove particles and contaminates. Cleaningsurfaces 314, 316 can include ultrasonic and/or megasonic cleaning.

One or more feedthroughs 318 can be formed through the substrate 312.The feedthrough 318 can be formed by forming a via 320 through thesubstrate 312. Although feedthrough assembly 310 includes twofeedthroughs 318, any suitable number of feedthroughs may be formed,e.g., 1, 2, 3, 4, 5, or more feedthroughs. Further, any suitabletechnique or combination of techniques can be utilized to form via 320,e.g., drilling, etching, laser drilling, etc.

Conductive material 322 can be formed in the via 320 as shown in FIG.7B. Any suitable technique or combination of techniques can be utilizedto form or dispose the conductive material 322 in the via 320, e.g.,plasma vapor deposition, chemical vapor deposition, physical vapordeposition (e.g., sputtering), plating, conductive composite pastes,etc. Further, the conductive material 322 may substantially fill the via320. In one or more embodiments, conductive material can be formed onone or more sidewalls of the via to form or dispose one or moreconductors within the via.

In one or more embodiments, one or both of the outer surface 314 and theinner surface 316 can be polished to remove any excess conductivematerial 322. Any suitable technique or combination techniques can beutilized to polish one or both surfaces 314, 316.

One or more conductors 350 can optionally be formed on at least one ofthe outer surface 314 and the inner surface 316. As illustrated in FIG.7C, conductors 350 are formed on the outer surface 314 of the substrate312. Any suitable technique or combination of techniques can be utilizedto form conductors 350. For example, in one or more embodiments,conductors 350 are formed by depositing a conductive material layer onthe outer surface 314 and the conductive material 322. The conductivematerial layer can be formed, e.g., using plasma vapor deposition,chemical vapor deposition, physical vapor deposition, etc. One or moreportions of the conductive material layer can then be removed to formthe conductors 350 using any suitable technique or combination oftechniques, e.g., photolithography, etc. In one or more embodiments, theconductors 350 are patterned such that the conductors remainelectrically coupled to conductive material 322 of via 320. Any suitablenumber of conductors 350 can be formed on the outer surface 314 and/orthe inner surface 316 of substrate 312.

In one or more embodiments, the conductors 350 are electrically coupledto the conductive material 322 in the vias 320. In such embodiments, theconductors 350 can be electrically coupled using any suitable technique,e.g., the electrical conductors are in physical contact with theconductive material. In one or more embodiments, the conductors 350 andthe conductive material 322 can include the same material or combinationmaterials. Further, in one or more embodiments, the conductors 350 andthe conductive material 322 can be formed or disposed simultaneously orsequentially.

One or more contacts can be formed on one or both of the outer surface314 and the inner surface 316 of substrate 312 using any suitabletechnique or combination of techniques. For example, as illustrated inFIG. 7D, a conductive material layer 331 can be disposed on and/orcoupled to the outer surface 314 over the conductors 350 (if present)and the vias 320. In an embodiment, the conductive material layer 331can comprise a conductive sheet or foil. The conductive material layer331 can be attached to the outer surface 314 of the substrate 312 usingany suitable technique or combination of techniques, e.g., forming abond that hermetically seals the conductive layer to the outer surface.Although not shown, a second conductive material layer can also beformed on the inner surface 316 and over the vias 320. In suchembodiments, the conductive material layers can be formed simultaneouslyon both surfaces of substrate 312 or sequentially. The conductivematerial layer 331 can be attached to the outer surface 314 asillustrated in FIG. 7D.

Any suitable technique or combination of techniques can be utilized toattach the conductive layer 331 to the outer surface 314, e.g., thetechniques described in U.S. Patent Application No. 62/096,706, entitledKINETICALLY LIMITED NANO-SCALE DIFFUSION BOND STRUCTURES AND METHODS.For example, electromagnetic radiation 370 can be directed throughsubstrate 312 from the inner surface 316 to an interface between theconductive layer 331, the conductors 350 (if present), and a surface ofthe substrate 312. The electromagnetic radiation 370 can form a bond(e.g., bond 40 of FIGS. 2 and 4) that hermetically seals the conductivelayer 331 to the substrate 312 in any suitable pattern or shape. Thebond can be a laser bond. In one or more embodiments, a bond surroundsthe via 320.

As illustrated in FIG. 7E, one or more portions of the conductivematerial layer 331 can be removed to form an external contact 332 on theouter surface 314 of the substrate 312. Any suitable technique orcombination of techniques can be utilized to form the external contacts332, e.g., photolithography, etching, laser ablation, etc. In one ormore embodiments, a mask or masks can be formed on the outer surface 314of the substrate 312, and the conductive material layer 331 can beformed over the mask. Portions of the conductive material layer 331 thatare formed on the mask itself can be removed using any suitabletechnique or combination of techniques, including photolithography,etching, laser ablation etc., to form external contacts 332. Inaddition, one or more portions of the conductive material layer 331 canalso be removed or patterned to create other electrical components, suchas an antenna.

The bond formed between the external contact 332 and the outer surface314 remains intact such that it hermetically seals the contact to theouter surface 314. In other words, portions of the conductive layer 331that are hermetically sealed to the outer surface 314 are not removedwhen the external electrodes 332 are patterned. Similar techniques canbe utilized to form internal contacts on the inner surface 316 of thesubstrate 312. The external contact 332 is electrically coupled to boththe conductors 350 (if present) and the conductive material 322 formedin the via 320. One or more feedthroughs 318 are thus formed through thesubstrate 312 to provide conductive pathways between the outer surface314 and the inner surface 316.

FIGS. 8A-E are schematic cross-section views of another method 400 offorming a feedthrough assembly 410. All of the design considerations andpossibilities regarding the feedthrough assembly 10 of FIGS. 1A-4 andfeedthrough assembly 310 of FIGS. 7A-E apply equally to the feedthroughassembly 410 of FIGS. 8A-E. One or more feedthroughs 418 can be formedthrough a substrate 412. A via 420 can be formed through the substrate412 between an outer surface 414 and an inner surface 416 of thesubstrate as shown in FIG. 8A. Any suitable technique or combination oftechniques can be utilized to form via 420. One or more conductors 450can be formed on at least one of the outer surface 414 and the innersurface 416 using any suitable technique or combination of techniques asshown in FIG. 8B. For example, in one or more embodiments, a conductivematerial layer can be formed on one or both of the outer surface 414 andinner surface 416, and the conductive material layer can be patterned toform conductors 450. The conductors 450 can include any suitableconductors, e.g., conductors 50 of assembly 10. The conductors 450 canbe formed such that they are electrically coupled to the via 420.

As shown in FIG. 8C, a conductive material layer 431 can be formed onthe outer surface 414 of the substrate 412. In one or more embodiments,the conductive material layer 431 can also be formed over one or more ofthe conductors 450 and one or more of the vias 420. Further, in one ormore embodiments, a conductive material layer can also be formed on theinner surface 416 of the substrate 412.

The conductive material layer 431 can be attached to the outer surface414 of the substrate 412 using any suitable technique or combination oftechniques. As illustrated in FIG. 8C, the conductive material layer 431is attached to the outer surface 440 by directing electromagneticradiation 470 through the inner surface 416 of the substrate 412 anddirecting the light at an interface of the conductive material layer 631and the outer surface 414. In one or more embodiments, the light 470 canbe directed and/or focused on the conductors 450 that are disposedbetween the conductive layer 431 and the outer surface 414. The light470 can form a bond between the conductive layer 431 and the outersurface 414 (e.g., bond 40 of FIGS. 2 and 4). In one or moreembodiments, the conductors 450 can also be attached to one or both ofthe conductive of layer 431 and the outer surface 414 along the bond.Bonding the conductors 450 along or within the bond can further enhanceelectrical coupling between the conductive layer and the conductors.Further, in one or more embodiments, the bond can hermetically seal theconductive layer 431 to the outer surface 414 of the substrate 412.

A portion or portions of the conductive material layer 431 can beremoved to form one or more external contact 432 on the outer surface414 of the substrate 412 as shown in FIG. 8D. These portions of theconductive material layer 431 can be removed using any suitabletechnique or combination of techniques. Any suitable technique orcombination of techniques can be utilized to form the external contacts432 including, for example, photolithography, etching, laser ablation,etc. In some embodiments, a mask or masks can be formed on the outersurface 414 of the substrate 412, and the conductive material layer 431can be formed over the mask. Portions of the conductive material layer431 that are formed on the mask itself can be removed using any suitabletechnique or combination of techniques to form external contacts 432. Inone or more embodiments, the bond formed between the conductive materiallayer 431 and the substrate 412 when the conductive material layer wasattached to the substrate remains between the external contact 432 andthe outer surface 414 of the substrate such that the external contact ishermetically sealed to the outer surface of the substrate.

Conductive material 422 can be formed in via 420 as shown in FIG. 8Eusing any suitable technique or combination of techniques. In one ormore embodiments, the conductive material 422 fills substantially all ofthe via 420 to provide a conductive pathway from the external contact432 and the conductors 450 on the outer surface 414 of the substrate 412to one or more conductors or contacts on the inner surface 416 or one ormore electronic devices disposed on the inner-surface side of thesubstrate. In one or more embodiments, conductive material 422 can formone or more conductors within the via to provide this conductivepathway. For example, the conductive material 422 can be disposed on oneor more sidewalls of the via 420 to provide a conductive pathway.Because the external contact 432 is hermetically sealed to the outersurface 414 of the substrate 412, the via 420 does not need to besubstantially filled with conductive material to hermetically seal thefeedthrough 418. Discrete conductors, therefore, can be formed in thevia 420.

The conductive material 422 is electrically coupled to the externalcontact 432. In one or more embodiments, the conductive material 422 canalso be electrically coupled to the conductors 450. Further, in one ormore embodiments, the conductive material 422 can also be formed on theinner surface 416 of the substrate to provide one or more conductors452. In one or more embodiments, a separate conductive material can beformed on the inner surface 416 to provide one or more conductors on theinner surface. The conductive material 422 can be disposed in the via420 and form conductors 452 either simultaneously or sequentially.

FIGS. 9A-E are schematic cross-section views of another embodiment of amethod 500 for forming a feedthrough assembly 510. All of the designconsiderations and possibilities regarding the feedthrough assembly 10of FIGS. 1A-4, feedthrough assembly 310 of FIGS. 7A-E, and feedthroughassembly 410 of FIGS. 8A-E apply equally to the feedthrough assembly 510of FIGS. 9A-E. In method 500, a conductive material layer 531 cancomprise a conductive sheet or foil as described in conjunction withFIGS. 7A-E. The conductive material layer 531 can be attached to theouter surface 514 of the substrate 512 using any suitable technique orcombination of techniques, e.g., forming a bond that hermetically sealsthe conductive layer to the outer surface. For example, as illustratedin FIG. 9A, electromagnetic radiation 570 is directed through innersurface 516 of the substrate 512 and directed at an interface of theconductive material layer 531 and the outer surface 514 to form one ormore bonds between the conductive material layer 531 and the outersurface.

One or more portions of the conductive material layer 531 can be removedto form one or more external contacts 532 on the outer surface 514 ofthe substrate 512 as shown in FIG. 9B. Any suitable technique orcombination of techniques can be utilized to form the external contacts532 including, for example, photolithography, etching, laser ablation,etc. In some embodiments, a mask or masks can be formed on the outersurface 514 of the substrate, and the conductive material layer 531 canbe formed over the mask. Portions of the conductive material layer 531that are formed on the mask itself can be removed using any suitabletechnique or combination of techniques to form external contacts 532. Inone or more embodiments, the bond formed when the conductive materiallayer 531 was attached to the substrate 512 remains between the externalcontact 532 and the outer surface 514 of the substrate 512 such that thecontact is hermetically sealed to the outer surface. Any suitabletechnique or combination of techniques can be utilized to form externalcontacts 532.

As shown in FIG. 9C, one or more vias 520 can be formed through thesubstrate 512. The via 520 can be formed such that it is within a closedshape or region defined by the bond such that the bond surrounds thevia. Because the via 520 is within the shapes or regions formed by thebonds, the via 520 can be protected from the external environment. Inone or more embodiments, an etch stop layer can be formed between theconductive material layer 531 and the outer surface 514 of the substrate512 to prevent the formation of the via 520 from removing portions ofthe external contact 532.

One or more conductors 550 can optionally be formed on the externalcontact 532 and/or on the outer surface 514 of the substrate 512 asshown in FIG. 9D. In one or more embodiments, one or more conductors 550can be electrically coupled to the external contact 532. Any suitabletechnique or combination of techniques can be utilized to formconductors 550. In one or more embodiments, the conductors 550 can beprovided by forming a conductive material layer over the externalcontact 532 and the outer surface 514. This conductive material layercan then be patterned to form conductor 550 in any desirableconfiguration.

As shown in FIG. 9E, conductive material 522 can be disposed in the via520 to provide a conductive pathway from the external contact 532 toconductors, contacts, electronic devices, etc. disposed on theinner-surface side of the substrate 512. Any suitable technique orcombination of techniques can be utilized to form the conductivematerial 522 in the via 520. As mentioned herein, the via 520 can besubstantially filled with the conductive material 522. In one or moreembodiments, the conductive material 522 can be disposed on a portion orportions of one or more sidewalls of the vias as shown in FIG. 9E.Further, one or more conductors 552 can optionally be formed on theinner surface 516 of the substrate 512 either simultaneously withforming conductive material in the vias or sequentially. In one or moreembodiments, the same material utilized for the conductive material 522can also be utilized to form conductors 552. Conductors 552 can beformed using any suitable technique or combination of techniques. Theoptional conductors 550 can be provided to, for example, electricallycouple an electronic device or contact disposed on the outer surface 514to the conductors 552, or a contact or electronic device on the innersurface 516.

The various embodiments of feedthrough assemblies described herein canbe utilized with any device or system that requires hermetically sealedconductive pathways. For example, one or more embodiments of feedthroughassemblies described herein can be utilized with an implantable medicaldevice or system. Nearly any implantable medical device or systememploying leads may be used in conjunction with the various embodimentsof feedthrough assemblies described herein. Representative examples ofsuch implantable medical devices include hearing implants, e.g.,cochlear implants; sensing or monitoring devices; signal generators suchas cardiac pacemakers or defibrillators, neurostimulators (such asspinal cord stimulators, brain or deep brain stimulators, peripheralnerve stimulators, vagal nerve stimulators, occipital nerve stimulators,subcutaneous stimulators, etc.), gastric stimulators; or the like.

For example, FIG. 10 is a schematic side view of one embodiment of animplantable medical device system 600. The system 600 includes animplantable medical device (IMD) 602, a lead 690, and a lead extension682. In one or more embodiments, the system 600 can also include afeedthrough assembly (e.g., feedthrough assembly 10 of FIGS. 1A-4).

The IMD 602 includes a connector header 604 adapted to receive aproximal portion 681 of the lead extension 682. The proximal portion 681of lead extension 682 includes one or more electrical contacts 684 thatare electrically coupled to internal contacts (not shown) at distalconnector 686 of the lead extension. The connector header 604 of the IMD602 includes internal contacts (not shown) and is adapted to receive theproximal portion 681 of the lead extension 682 such that the internalcontacts of the connector header may be electrically coupled to thecontacts 684 of the lead extension when the lead extension is insertedinto the header.

The system 600 depicted in FIG. 10 further includes lead 690. Thedepicted lead 690 has a proximal portion 691 that includes contacts 692and a distal portion 693 that includes electrodes 694. Each of theelectrodes 694 can be electrically coupled to a discrete contact 692.The distal connector 686 of the lead extension 682 is adapted to receivethe proximal portion 691 of the lead 690 such that the contacts 692 ofthe lead may be electrically coupled to the internal contacts of theconnector of the extension. Accordingly, a signal generated by the IMD602 can be transmitted to a tissue of a patient by an electrode 694 oflead 690 when the lead is connected to the extension 682 and theextension is connected to the IMD. Alternatively or in addition, asignal received by electrode 694 of lead 690 from a patient may betransmitted to a contact of the IMD 602 when the lead is connected tothe extension 682 and the extension is connected to the IMD.

It will be understood that lead 690 can be coupled to IMD 602 withoutuse of an extension 682. Any number of leads 690 or extensions 682 canbe coupled to device 602. While lead 690 is depicted as having fourelectrodes 694, it will be understood that the lead can include anynumber of electrodes, e.g. 1, 2, 3, 4, 5, 6, 7, 8, 16, 32, or 64electrodes. Corresponding changes in the number of contacts 692 in lead690, contacts 684 and internal contacts in connector 686 of leadextension, or internal contacts in header 604 of device 602 may berequired or desired.

As used hereinafter, “lead” will refer to both “leads” and “leadextensions” unless the content and context clearly dictates otherwise.

FIG. 11 is a schematic cross-section view of the IMD 602 of FIG. 10. TheIMD 602 further includes a hermetically sealed housing 603 in whichelectronics 606 are disposed, and the connector header 604 disposed onor attached to the housing. The housing 603 can include any suitablematerial or combination of materials, e.g., titanium, glass, sapphire,etc. In one or more embodiments, the housing 603 can be electricallyconductive to provide a ground electrode for the IMD 602 as is known inthe art. A lead receptacle 605 is formed in a housing 607 of the header604. The receptacle 605 is adapted to receive and electrically couple tocontacts 684 of the lead extension 682 (or contacts 692 of the lead690).

The receptacle 605 has internal contacts 609 positioned to align withand electrically couple with contacts 684 of the lead extension 682and/or contacts 692 of the lead 690 when the lead extension or lead isproperly inserted into the receptacle. The pitch of the internalcontacts 609 of FIG. 11 is adapted to allow electrical connectionbetween the contacts 684 of the lead extension 682 or contacts 692 oflead 690.

Electronics 606 are adapted to send electrical signals to a tissue of apatient, or receive signals from a tissue of a patient, through leadsoperably coupled to the electronics of the IMD 602. As used herein, theterm “transmitted electrical signals” is used to refer to both thesignals sent by electronics 606 to tissue of the patient or received bythe electronics from the tissue of the patient. In one or moreembodiments, the feedthrough assembly 610 is electrically coupled to theelectronics 606. For example, conductors 608 of IMD 602 can beelectrically coupled to internal contacts 609 of lead receptacle 605 viafeedthroughs 618 of feedthrough assembly 610, which extend throughhermetically sealed housing 603. For example, in one or moreembodiments, conductor 608 can be electrically coupled to theelectronics 606 and an internal contact 636 of feedthrough 618. Theinternal contact 636 can be electrically coupled to external contact 632of the feedthrough assembly 618 through conductive material disposed ina via 620. The external contact 632 can in turn be electrically coupledto the internal contact 609 of lead receptacle 605 by conductor 601. Aconductive pathway is, therefore, formed between the internal contact609 of lead receptacle 605 and electronics 606. Feedthrough assembly 610can include any feedthrough assembly described herein, e.g., feedthroughassembly 10 of FIGS. 1A-4.

In one or more embodiments, each conductor 608 can electrically couplean internal contact 609 of the lead receptacle 605 to a discrete channelof the electronics 606. As used herein, a “channel” of the electronicsis a discrete electronic pathway through which signals may betransmitted independently of another channel. The feedthroughs 618 canbe electrically coupled with internal contacts 609 via welding,soldering, brazing, coupling via conductive wires, or the like. Eachchannel of the electronics 606 can be independently coupled with adiscrete internal contact 609 of a receptacle, which can be coupled witha discrete contact 684 of the lead extension 682 or contact 692 of thelead 690, which can be coupled with a discrete electrode 694 of thelead. Accordingly, each channel of the electronics 606 can be operablycoupled to a given electrode 694 of a lead.

The feedthrough assembly 610 can be disposed within the header 604 suchthat the housing 607 surrounds the assembly, and the assembly can beattached to a sidewall of the housing 603 of the IMD 602 between theheader and the housing. In one or more embodiments, the feedthroughassembly 610 can be disposed on any sidewall of the housing such thatthe system does not include a header. The feedthrough assembly 610 canbe disposed on a sidewall of the housing 603 using any suitabletechnique or combination of techniques. In one or more embodiments whena header is not utilized, the feedthrough assembly 610 can be coveredwith an insulative covering (e.g., silicone).

FIG. 12 is a schematic cross-section view of a portion of one embodimentof an implantable medical device system 700. All of the designconsiderations and possibilities regarding the system 600 of FIGS. 10-11apply equally to the system 700 of FIG. 12. As illustrated in FIG. 12, aweld ring 760 of feedthrough assembly 710 can be attached to housing 703of IMD 702. Feedthrough assembly 710 can include any feedthroughassembly described herein, e.g., feedthrough assembly 10 of FIGS. 1A-4.Any suitable technique or combination of techniques can be utilized toattach the assembly 710 to the housing 703. In one or more embodiments,the weld ring 760 can be hermetically sealed to the housing 703 by abond (e.g., laser bond) between the housing and the weld ring. Anysuitable technique or combination of techniques described herein can beutilized to form the bond.

In one or more embodiments, a feedthrough assembly does not include aweld ring, and a substrate of the assembly can be directly attached to ahousing of an implantable medical device. For example, FIG. 13 is aschematic cross-section view of another embodiment of an implantablemedical device system 800. All of the design considerations andpossibilities regarding the system 600 of FIGS. 10-11 apply equally tothe system 800 of FIG. 13. In the illustrated embodiment, feedthroughassembly 810 of system 800 is attached to housing 803 of implantablemedical device 802 without the use of a weld ring. Feedthrough assembly810 can include any suitable feedthrough assembly described herein,e.g., feedthrough assembly 10 of FIGS. 1A-4. In one or more embodiments,the housing 803 of the implantable medical device 802 can behermetically sealed to substrate 812 of the feedthrough assembly 810 bya bond (e.g., laser bond) between the housing and the substrate 812. Thebond can be formed using any suitable technique or combination oftechniques described herein. See also the techniques described inco-owned U.S. Pat. No. 8,796,109 to Ruben et al.

FIGS. 14A-B depict another alternative embodiment of a feedthroughassembly 1610. For ease of discussion, the elements that are common toFIGS. 1A & 1B and FIGS. 14A-B are numbered with identical referencedesignators. All of the design considerations and possibilitiesregarding the feedthrough assembly 10 of FIGS. 1A-4 apply equally to thefeedthrough assembly 1610 of FIGS. 14A-B. Assembly 1610 includesfeedthroughs 18. Each feedthrough 18 includes an external contact 32that can be electrically coupled to an internal contact, conductor, ordevice. For example, the external contact 32 can be electrically coupledto internal contact 36 as described with reference to FIGS. 1A-4.

As those skilled in the art can appreciate, the assembly 1610 can beelectrically coupled to any suitable device or devices that are externalto the package 1602. For example, in one or more embodiments, thepackage 1602 can be electrically coupled to a lead of an implantablemedical device. In some situations, such lead wires effectively act asan antenna and thus tend to collect stray or electromagneticinterference (EMI) signals for transmission to the interior of thepackage 1602 and onto electronic components and circuitry that areelectrically coupled thereto. Such EMI signals may interfere with theproper operation of the electronic components and circuitry.

To mitigate the deleterious effect of the EMI signals, one or more ofthe external contacts 32 can optionally be coupled to a capacitor 1636.The capacitor 1636 shunts any EMI signals from the exterior of theassembly 1610. In particular, the capacitor 1636 is coupled to via 20 tosuppress and/or prevent transfer of such EMI signals from the outersurface 14 to the interior of the assembly 1610 through the conductivepathway defined by the via 20. In operation, the capacitor 1636 permitspassage of relatively low frequency electrical signals from the exteriorof the assembly 1610, while shunting and shielding undesiredinterference signals of typically high frequency to the components thatare coupled to the capacitor 1636 in the interior of the assembly 1610.

The capacitor 1636 includes an insulator 1638 that is disposed between afirst conductor 1640 and a second conductor 1642. The first conductor1640 may be formed utilizing any suitable technique such as thetechniques described with reference to the contact 36, including but notlimited to copper, titanium, aluminum, chromium, nickel, gold,composites (e.g., silver-filled epoxies), and combinations thereof.First conductor 1640 can include any suitable material or combinationmaterials, e.g., any of the conductive materials described herein, suchas the same materials utilized for contact 36. Insulator 1638 is formedfrom any suitable dielectric material such as silicon dioxide, siliconnitride, tantalum pentoxide, or barium strontium titanate. These may beformed using standard thin film techniques such a chemical vapordeposition, atomic layer deposition, printing, dispensing or laminating.A second conductor 1642 is formed on the insulator 1638, through forexample, internal metallization of one or more conductive material(s)directly onto the non-conductive material of insulator 1638. Thematerials selection for the second conductor 1642 can include one ormore of the materials used to form the conductor 36, including but notlimited to copper, titanium, aluminum, chromium, nickel, gold,composites (e.g., silver-filled epoxies), and combinations thereof. Itshould be noted that the depiction of the capacitor 1636 as being a twoplate capacitor is solely provided for ease of description and is notintended to be limited as such. Rather, it is contemplated thedisclosure can be extended to applications where the capacitors 1636include any number of plates, such as two or more plates, depending onthe desired capacitance for any given implementation.

FIGS. 15A-E are schematic cross-section views of another embodiment of amethod 1700 for forming a feedthrough assembly 1710. All of the designconsiderations and possibilities regarding the feedthrough assembly 10of FIGS. 1A-4, feedthrough assembly 310 of FIGS. 7A-E, feedthroughassembly 410 of FIGS. 8A-E, feedthrough assembly 510 of FIGS. 9A-E, andfeedthrough assembly 1610 of FIGS. 14A-B apply equally to thefeedthrough assembly 1710 of FIGS. 15A-E. In method 1700, a conductivematerial layer 1731 can be disposed on and/or coupled to an outersurface 1714 of a substrate 1712. The conductive material layer 1731 cancomprise a conductive sheet or foil. The conductive material layer 1731can be attached to the outer surface 1714 of the substrate 1712 usingany suitable technique or combination of techniques, e.g., forming abond that hermetically seals the conductive layer to the outer surface.For example, as illustrated in FIG. 15A, electromagnetic radiation 1770is directed through inner surface 1716 of the substrate 1712 anddirected at an interface of the conductive material layer 1731 and theouter surface 1714 to form one or more bonds between the conductivematerial layer 1731 and the outer surface.

One or more portions of the conductive material layer 1631 can beremoved to form one or more external contacts 1632 on the outer surface1614 of the substrate 1612 as shown in FIG. 15B. Any suitable techniqueor combination of techniques can be utilized to form the externalcontacts 1632 including, for example, photolithography, etching, laserablation, etc. In some embodiments, a mask or masks can be formed on theouter surface 1614 of the substrate, and the conductive material layer1631 can be formed over the mask. Portions of the conductive materiallayer 1631 that are formed on the mask itself can be removed using anysuitable technique or combination of techniques to form externalcontacts 1632. In one or more embodiments, the bond formed when theconductive material layer 1631 was attached to the substrate 1612remains between the external contact 1632 and the outer surface 1614 ofthe substrate 1612 such that the contact is hermetically sealed to theouter surface. Any suitable technique or combination of techniques canbe utilized to form external contacts 1632.

As shown in FIG. 15C, one or more vias 1720 can be formed through thesubstrate 1712. The via 1720 can be formed such that it is within aclosed shape or region defined by the bond such that the bond surroundsthe via. Because the via 1720 is within the shapes or regions formed bythe bonds, the via 1720 can be protected from the external environment.In one or more embodiments, an etch stop layer can be formed between theconductive material layer 1731 and the outer surface 1714 of thesubstrate 1712 to prevent the formation of the via 1720 from removingportions of the external contact 1732.

One or more conductors 1750 can optionally be formed on the externalcontact 1732 and/or on the outer surface 1714 of the substrate 1712 asshown in FIG. 15D. In one or more embodiments, one or more conductors1750 can be electrically coupled to the external contact 1732. Anysuitable technique or combination of techniques can be utilized to formconductors 1750. In one or more embodiments, the conductors 1750 can beprovided by forming a conductive material layer over the externalcontact 1732 and the outer surface 1714. This conductive material layercan then be patterned to form conductor 1750 in any desirableconfiguration.

As shown in FIG. 15E, conductive material 1722 can be disposed in thevia 1720 to provide a conductive pathway from the external contact 1732to conductors, contacts, electronic devices, etc. disposed on theinner-surface side of the substrate 1712. Any suitable technique orcombination of techniques can be utilized to form the conductivematerial 1722 in the via 1720. As mentioned herein, the via 1720 can besubstantially filled with the conductive material 1722. In one or moreembodiments, the conductive material 1722 can be disposed on a portionor portions of one or more sidewalls of the vias as shown in FIG. 15E.

Further, one or more EMI filtering capacitors can optionally be formedon the inner surface 1716 of the substrate 1712. Accordingly, one ormore first conductors 1760, corresponding to the number of desiredcapacitors, can be formed either simultaneously with forming conductivematerial in the vias or sequentially. In one or more embodiments, thesame material utilized for the conductive material 1722 can also beutilized to form first conductors 1760. First conductors 1760 can beformed using any suitable technique or combination of techniques.Subsequently, insulator 1762 is coupled to the first conductor 1760using any suitable techniques, such as chemical vapor deposition, plasmavapor deposition, physical vapor deposition. The same techniques maysimilarly be utilized to couple a second conductor 1764 to the insulator1762. As such, the first and second conductors 1760, 1764 and theinsulator 1762 define a capacitor structure that is formed on the innersurface 1716 of substrate 1712.

All headings provided herein are for the convenience of the reader andshould not be used to limit the meaning of any text that follows theheading, unless so specified.

The terms “comprises” and variations thereof do not have a limitingmeaning where these terms appear in the description and claims. Suchterms will be understood to imply the inclusion of a stated step orelement or group of steps or elements but not the exclusion of any otherstep or element or group of steps or elements.

The words “preferred” and “preferably” refer to embodiments of thedisclosure that may afford certain benefits, under certaincircumstances; however, other embodiments may also be preferred, underthe same or other circumstances. Furthermore, the recitation of one ormore preferred embodiments does not imply that other embodiments are notuseful, and is not intended to exclude other embodiments from the scopeof the disclosure.

In this application, terms such as “a,” “an,” and “the” are not intendedto refer to only a singular entity, but include the general class ofwhich a specific example may be used for illustration. The terms “a,”“an,” and “the” are used interchangeably with the term “at least one.”The phrases “at least one of” and “comprises at least one of” followedby a list refers to any one of the items in the list and any combinationof two or more items in the list.

The phrases “at least one of” and “comprises at least one of” followedby a list refers to any one of the items in the list and any combinationof two or more items in the list.

As used herein, the term “or” is generally employed in its usual senseincluding “and/or” unless the content clearly dictates otherwise. Theuse of the term “and/or” in certain portions of this disclosure is notintended to mean that the use of “or” in other portions cannot mean“and/or.”

The term “and/or” means one or all of the listed elements or acombination of any two or more of the listed elements.

As used herein in connection with a measured quantity, the term “about”refers to that variation in the measured quantity as would be expectedby the skilled artisan making the measurement and exercising a level ofcare commensurate with the objective of the measurement and theprecision of the measuring equipment used. Herein, “up to” a number(e.g., up to 50) includes the number (e.g., 50).

Also herein, the recitations of numerical ranges by endpoints includeall numbers subsumed within that range as well as the endpoints (e.g., 1to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, 5, etc.).

All references and publications cited herein are expressly incorporatedherein by reference in their entirety into this disclosure, except tothe extent they may directly contradict this disclosure. Illustrativeembodiments of this disclosure are discussed and reference has been madeto possible variations within the scope of this disclosure. These andother variations and modifications in the disclosure will be apparent tothose skilled in the art without departing from the scope of thedisclosure, and it should be understood that this disclosure is notlimited to the illustrative embodiments set forth herein. Accordingly,the disclosure is to be limited only by the claims provided below.

What is claimed is:
 1. A feedthrough assembly comprising anon-conductive substrate and a feedthrough, the feedthrough comprising:a via from an outer surface to an inner surface of the non-conductivesubstrate; a conductive material disposed in the via; and an externalcontact disposed over the via on the outer surface of the non-conductivesubstrate, wherein the external contact is electrically coupled to theconductive material disposed in the via, and wherein the externalcontact is hermetically sealed to the outer surface of thenon-conductive substrate by a laser bond surrounding the via.
 2. Theassembly of claim 1, wherein the feedthrough further comprises aninternal contact disposed over the via on the inner surface of thenon-conductive substrate, wherein the internal contact is electricallycoupled to the conductive material disposed in the via, and wherein theinternal contact is attached to the inner surface of the non-conductivesubstrate by a laser bond that surrounds the via.
 3. The assembly ofclaim 1, wherein the laser bond that hermetically seals the externalcontact to the outer surface of the non-conductive substrate comprises abond line.
 4. The assembly of claim 3, wherein the bond line thathermetically seals the external contact to the outer surface of thenon-conductive substrate comprises an interfacial layer between theexternal contact and the non-conductive substrate.
 5. The assembly ofclaim 4, wherein the interfacial layer has a thickness in a directionnormal to the outer surface of the non-conductive substrate of nogreater than 10 μm.
 6. The assembly of claim 1, wherein thenon-conductive substrate is substantially transmissive to light having awavelength of between 1 nm and 30 μm.
 7. The assembly of claim 1,wherein the non-conductive substrate comprises at least one of glass,quartz, silica, sapphire, silicon carbide, diamond, and gallium nitride,and alloys or combinations thereof.
 8. The assembly of claim 1, whereinthe external contact comprises at least one of copper, silver, titanium,niobium, zirconium, tantalum, stainless steel, platinum, iridium, andalloys or combinations thereof.
 9. The assembly of claim 1, wherein theexternal contact comprises a thickness in a direction normal to theouter surface of the non-conductive substrate of at least 10micrometers.
 10. The assembly of claim 1, further comprising a weld ringhermetically sealed to the outer surface of the non-conductive substrateby a laser bond adjacent a perimeter of the substrate, wherein the weldring surrounds the external contact.
 11. The assembly of claim 1,further comprising an electronic device disposed on the inner surface ofthe non-conductive substrate, wherein the electronic device iselectrically coupled to the conductive material in the via of thefeedthrough, and wherein the electronic device is attached to thenon-conductive substrate by a bond.
 12. The assembly of claim 11,wherein the electronic device comprises an integrated circuit.
 13. Theassembly of claim 1, wherein the via comprises an opening at the outersurface of the non-conductive substrate that has a diameter of nogreater than 500 micrometers.
 14. The assembly of claim 1, wherein thelaser bond that hermetically seals the external contact to the outersurface of the non-conductive substrate comprises a bond line that formsa closed shape in a plane parallel to the outer surface of thenon-conductive substrate.
 15. The assembly of claim 1, furthercomprising a conductor disposed on the outer surface of thenon-conductive substrate and electrically coupled to the externalcontact.
 16. The assembly of claim 1, wherein the non-conductivesubstrate is substantially transmissive to a transmitted light having apre-determined magnitude such that the energy transmitted through thesubstantially transparent substrate material is at least one of:sufficient to activate the bonding process at the interface viaabsorption by the opaque material, and absorbable by the transparentmaterial without melting, distorting, or otherwise modifying the bulkproperties of the transparent material away from the bonding region. 17.The assembly of claim 1, wherein the feedthrough further comprises afiltering capacitor electrically coupled to the via on the inner surfaceof the non-conductive substrate, wherein the filtering capacitorcomprises a dielectric member interposed between two conductive layers.18. A feedthrough assembly comprising a non-conductive substrate and afeedthrough, the feedthrough comprising: a via from an outer surface toan inner surface of the non-conductive substrate; a conductive materialdisposed in the via; and an external contact disposed over the via onthe outer surface of the non-conductive substrate, wherein the externalcontact is electrically coupled to the conductive material disposed inthe via, and wherein the external contact is hermetically sealed to theouter surface of the non-conductive substrate by a bond line surroundingthe via.